This invention belongs to the field of agricultural chemistry and relates to the protection of plants from disease.
Agricultural chemical research has produced a great number of plant protective agents, and research continues to produce new ones every year. A number of publications have disclosed plant-protective compounds which constitute the background of this invention.
For example, British Pat. No. 845,916 discloses that a family of N,N-dialkylanilines, which can bear three nitro groups, are useful as plant fungicides.
Roberts, Ind. Eng. Chem. 34, 497-498 (1942), and Goldsworthy et al., J. Ag. Research 64, 667-678 (1942) discussed phytopathological testing of diphenylamine compounds including 2,4-diaminodiphenylamine and 4-nitrodiphenylamine.
Belgian Pat. No. 780,549 discloses halo-substituted diphenylamines which can bear nitro groups. However, the Belgian patent describes compounds containing at least four halogen atoms, and the phenyl rings of the compounds are alternatively substituted with a variety of groups such as carboxy, sulfonamido, perhalocarbyl, hydrocarbylamino and so forth.
German Offenlegungsschrift No. 2,363,602, published June 27, 1974, describes a group of diphenylamines having diverse substituents, some of which are the same as the substituents of the compounds of this invention.